#!/bin/bash
# using select in the menu

function diskspace {
   clear
   df -k
}

function whoseon {
   clear
   who
}

function memusage {
   clear
   cat /proc/meminfo
}

PS3="Enter option: "
select option in "Display disk space" "Display logged on users"¬
"Display memory usage" "Exit program"
do
   case $option in
   "Exit program")
         break ;;
   "Display disk space")
         diskspace ;;
   "Display logged on users")
         whoseon ;;
   "Display memory usage")
         memusage ;;
   *)
         clear
         echo "Sorry, wrong selection";;
   esac
done
clear
